Ugh. There's no other word that completely expresses our impressions of Ego & Company's Slide Case for iPhone 4 ($35), a new accessory that trumps the worst wasteful packaging practices we've previously seen by literally doubling them. Two separate hard plastic boxes and cardboard wrappers are unnecessarily used to hold the top and bottom halves of the Slide Case, cumulatively giving you more stuff to throw away (or hopefully recycle) than keep. Seemingly…